Medical Engineer

ADVANCES N THE SCIENCE OF MEDICINE

Running injuries and what the biomechanics of the human body tells us to prevent them

Running is without doubt the most popular of cardiovascular exercises. It forms an integral part of any serious fitness regime, and millions partake in the activity every year, be it for sport, training or just losing weight.

And yet, there is a serious downside to running most of us are not aware of. While it provides us with a variety of health-related benefits, studies show that around 60 percent of all runners experience some sort of lower-extremity injury due to the activity.
The critical areas usually affected are your knees and ankles. Most of the running injuries are due to overuse, which occurs when your muscles, bones and joints are repeatedly subjected to high stress. The cumulative effect of these stresses can cause structural damage at a greater rate than at which the body can repair itself.

But running is not the actual cause of such problems. In fact, if you?re free from any joint-trouble and arthritis, and have not just come off the operation table with a serious operation to knee or ankle, the only factor causing just injuries is your running form. Many of us do not realize that not only do we need proper footwear and a suitable running track (hard pavement just wont do, it subjects your lower body to far greater stress), but we also need proper running form.

When analyzing how a person runs, we essentially look at their biomechanics and observe how optimal their motion is. In other words, you?re looking at both the mechanical aspects of human motion and the efficiency of a person?s running technique. If a runner can minimize the stress to their lower body induced through regular running by simply maintaining proper form and technique (and obeying certain biomechanical principles), injuries resulting from running become rare.

The study of biomechanics deals with three important aspects: safety (freedom from injury), effectiveness (optimal level of performance) and efficiency (minimal effort for maximum output). When applied to running, most runners (especially if you run for sport), concentrate on effectiveness and efficiency. A thorough understanding of how the human body functions during motion can help trainers devise methods and programs through which runners can improve their performances (effectiveness) while conserving their strength (efficiency).

But what about safety? Everyone knows that you need to stretch before you run, to reduce the chances of cramps and poor running form later on. Most of us also try to adhere to proper footwear (running shoes instead of basketball shoes), and stick to designated running tracks where possible. However, the question of running technique is often overlooked and ignored. This has much to do with how we learn to run.

Since that happens at an early age, little thought is put into the biomechanics of the activity. But how you run is critically important in the way that stress is distributed throughout the body. Simple things such as how your feet hit the ground and how your knees should bend during that time are major factors in determining how much stress is put on your body.

For example, roughly 80 percent of all runners strike the ground heel first. In heel-strike running, two problems occur. First, the leg is fairly stiff at the point of impact, resulting in a high level of shock to your knees. Second, heel-strike running results in extra pressure being put on the ankle. The result is heightened stress to your body, and a greater chance of injury through repetitive movement.

Instead, one should strike the ground with the midfoot (a practice supported by the majority of elite runners). This requires that you flex your leg upon impact, thus reducing the direct stress to your knees, as well as avoiding the extra pressure that heel-strike puts on your ankles.

However, this is effectively a totally new method of running for our body, and one has to unlearn basic motor patterns that haven been established since childhood. The benefits, though, are obvious. A greatly reduced risk of injury is a building block for serious running, be it for sport or fitness. Combined with proper motion techniques learned from a biomechanical analysis, you can easily learn to run safer, faster, and better.